Re: External Queue

[Nicholas Beser <beser@aplcomm.jhuapl.edu>]

Chris Albertson wrote:

>
> The only problem here is that if mira, your data reduction computer,
> is slow.  (I think you said it is a SPARC 2.Which is kind of like a
> loaded 486 but with better I/O and graphics.)

It's more like a low end Pentium (60Mhz). I timed the conversion process last
night. It took about 13 seconds to convert a FITS file to raw, convert the raw to
pgm, create a 1/4 scale pgm, and then compress both pgm files to jpeg. I also wrote
a small routine (parsename) that examined the file name, determined that it was CCD
0,1, or 2 and then copied them to the file name latest_ccd#.jpg or
latest_ccd#.s.jpg and placed them in the web image directory. While the script
worked fine running it at mira, it had problems running the parsename routine from
tass. I think it might have worked better if I wrote it in perl.

I also have 5 of these rather slow sparc stations. So it would not be unreasonable
to have one dedicated to each sensor (parallel processing).

The issue will be the automated star list generation. If it can be completed in 12
minutes or less per channel, then we could have the lists available in real time as
well. I have access to more sparc 2's so if I add two more, I could run them with a
processing time of 24 minutes. I don't think it would be that slow.

>
> One advantage of this setup, even if your data processing computer
> is fast, is that you can shut it down and restart it or add a second
> (or third) data processing computer.  The systems are "loosely
> coupled" and the system scales:  You can add more real-time data
> collectors or more data reduction computers as required.  We don't
> need this -- yet.  But I was thinking down the line when some
> one will be running a four color Mark IV system and maybe a
> Mark III triplet all at once.

My thoughts exactly. It should be possible to have the data processed
automatically, and distribute the star lists. We need to work up some common
approach for the Mark III automated data analysis as a prototype for the Mark IV
data.

Nick